In the manufacture of woven fabrics on an automatic weaving loom, a plurality of warp yarns or other strand material from a warp beam are threaded through a plurality of harness frames containing heddle assemblies which are vertically reciprocated to form the warp shed. Fill yarns are inserted into the shed by suitable insertion means, such as shuttles, to form the fabric. By varying the movements of the harness frames in accordance with pattern control means, fabrics of various woven construction are produced.
A harness frame of a weaving loom is of generally rectangular shape and has upper and lower vertically spaced, horizontal support members interconnected at their ends by vertical support members. Supported within the frame is a heddle assembly, comprising a planar array of heddles, or wires, containing eyelets through which individual warp yarn ends are threaded. The heddles are supported at their upper and lower ends on elongate heddle support rails, or bars, which extend closely adjacent and parallel to the upper and lower horizontal frame support members and are attached thereto by suitable means, such as heddle bar support plates. To provide stability to the harness frame and heddle assembly, the upper and lower support members of the harness frame are interconnected intermediate their ends and across the planar heddle array by one or more rigid centerstays.
For a particular pattern weave and width of fabric to be produced, the harness centerstays and heddle assembly are adjustably positioned and secured to the harness frame. The heddle bars and their attaching support plates also may be removed and repositioned in the harness frame for replacement of individual heddles of the heddle assembly.
In the past, positional adjustment of the centerstays and heddle assembly of a harness frame has been accomplished by manually positioning the centerstays and heddle bars with their support plates along channels or guideways in the upper and lower frame support members, with securement of the ends of each centerstay and each heddle bar plate to the frame members by mechanical locking devices, such as bolts or screws. Such adjustment requires that a loom operator individually position and mechanically secure the ends of each centerstay and each heddle bar support plate to the upper and lower frame members across the full width of the harness frame. Adjustable positioning and individual securement of the ends of each centerstay and each heddle bar support plate obviously is time-consuming in the weaving and preparing operation. Further, it is particularly difficult to reach the area of the lower horizontal support members of the frames when the harness assembly is threaded with the warp yarns. One such form of harness frame requiring securement of the individual supporting elements of the centerstays and heddle bars to the frame members is disclosed in my prior U.S. Pat. No. 3,221,776.